A friend of the McCanns said: "We understand it is a serialised drama but neither Kate, Gerry nor their holiday friends and main players have co-operated in any shape or form. And we have no idea who the actors are.

"We believe it is coming out very soon, within the next two weeks and before the next anniversary.

"Netflix had been hoping to screen it last year but the project took them a lot longer than expected. They had been wanting to string it out over eight episodes but it may now be a one or two parter."